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Assistant Professor

Location:
Chennai, Tamil Nadu, India
Posted:
May 24, 2018

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Resume:

*

Dear Sir/Madam,

Sub. : Application for Assistant Professor Position on PHYSICS in your esteemed

University– Reg.

I wish to introduce myself as Postdoctoral Research Associate (June 2016 - Till date), under CAS President International Fellowship at Xinjiang Technical Institute of Physics, Urumqi – China. The project working on Synthesis and Characterization on Deep UV and IR Nonlinear optical single crystal for structure-property relationships and devices in new optical-electronic functional materials. I also worked as a Postdoctoral Research Associate

(March-November 2013) Rensselaer Polytechnic Institute, Troy, New York, USA. The project work on flux growth of trivalent rare earth activated SrGaS, CaGaS, and MgGaS phosphor crystals for high efficacy LEDs by Solid State reaction and flux growth. I have been worked as a Post Doctoral Fellow (Sep 2009 – Feb. 2013), Department of Physics, Pukyong National University, Busan – South Korea. I have also one year experience (Sep 2008 – Aug 2009) Post Doctoral Fellow in Center for Condensed Matter Science, National Taiwan University, Taiwan. I completed my Ph.D. under the supervision of Prof. C. K. Jayasankar, Dept. of Physics, Sri Venkateswara University, Tirupati, India. My thesis title is, "Synthesis and Characterization of Transition metal doped ZnS Diluted Magnetic Semiconductor Nanomaterials".

I possess expertise in preparation and characterization of optical, magnetic nanomaterials, nonlinear optical properties, Phosphor, and dye-sensitized solar cells. I have hands on experience in operating X-ray diffraction, single crystal XRD, SEM, TEM, Optical absorption, Photoluminescence (PL), Micro-Raman, ESR, SQUID, impedance analyzer, Hall effect, XPS, Cyclic voltammetry (CV) and FTIR instruments. I have published Forty One papers in internationally reputed journals and presented seven research articles in International/National conferences and workshops. Here I am attaching my curriculum vitae, for your kind perusal and consideration.

Thank you for your consideration. Greatly looking forward to hearing from you soon. Thanking you

Yours sincerely,

Dr. S. SAMBASIVAM

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CURRICULUM VITAE

Dr. SANGARAJU SAMBASIVAM

Postdoctoral Research Associate

CAS President International Fellowship

Xinjiang Technical Institute of Physics

Urumqi – CHINA.

Email : ac5lta@r.postjobfree.com

Mobile :+86-152********

Personal Information

Date of Birth : 30th May, 1979

Gender : Male

Martial status : Married

Father’s Name : S. Subramanyam

Nationality : Indian

Academic Qualification : M. Sc. (Physics), M. Phil., Ph. D Languages known : English, Telugu, Tamil

Permanent Address : Dr. S. Sambasivam

Billakuppam (village)

S. R. Kandigai (post)

Gummidipoondi (taluk)

Thiruvallur (dist.)

Pin: 601201- Tamil Nadu – India.

Educational Qualification Details :

Ph. D. (Physics), Sri Venkateswara University, Tirupati, India, (2004 - 2008).

M. Phil. (Theoretical Physics), University of Madras, Chennai, India, (2002 - 2003).

M. Sc. (Physics), University of Madras, Chennai, India, (2000 - 2002).

B. Sc. (Physics), L.N.G. Govt. College, University of Madras, Chennai, India, (1997 - 2000).

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FELLOWSHIPS AWARDED

* 2005 - 2007: Junior Research Fellowship (University Grants Commission, New Delhi, India).

Research Experience:

For the past nine years, I have acquired expertise in preparation and characterization of Diluted Magnetic Semiconductor and Phosphors nanomaterials. I also have considerable expertise in growing single crystals of ZnCrTe by Bridgman growth technique. I have used characterization techniques such as XRD, SEM, EDAX, TEM, AFM, ESR, Optical absorption, Photoluminescence, Micro-Raman, VSM, SQUID, Hall effect, Mossbauer, Dielectric Studies, FTIR, DSC and TGA analysis systematically. I have so far published Forty One papers in International Journals; four more papers have been communicated. I have also presented for International/National conferences. The details are presented below. I had completed my Ph. D degree (June-2008) with the thesis entitled "Studies on Diluted Magnetic Semiconductors: Synthesis and Characterization of Cu and Fe doped ZnS nanoparticles" under the supervision of Prof. C. K. Jayasankar, Dept. of Physics, Sri Venkateswara University, Tirupati, India.

Postdoc Experience from 2008 to Till date:

1. September 2008 – August 2009

Post Doctoral Fellow in Centre for condensed Matter Sciences, National Taiwan University, Taipei, Taiwan.

The project entitled “Transition metal doped SnO2 magnetic nanoparticles by Sol-Gel method”.

2. September 2009 – February 2013

Post Doctoral Research Associate in Department of Physics, Pukyong National University, Busan – South Korea.

The project entitled “Rare earth metals (Er, Dy, Gd) doped SnO2 magnetic nanoparticles by Sol-Gel and Spray Pyrolysis technique. I have also working on Mn3O4, CuO nanorods and nanowires by hydrothermal technique.

3. March – November 2013

Post Doctoral Research Associate in Department of Electrical Engineering, Rensselaer Polytechnic Institute, New York – USA.

The project entitled “Single crystals phosphors by flux growth technique for LEDs applications”. 4

4. December 2013 – June 2014

Post Doctoral Research Associate in Department of Mechanical Engineering, Pusan National University, Pusan – South Korea.

The project entitled “Synthesis of oxides nanomaterials for Fuel Cell applications”. 5. August 2014 – September 2015

Assistant Professor in Department of Physics, Velammal Institute of Technology, Chennai – India. 6. October 2015 – May 2016

Assistant Professor in Department of Applied Physics, Adama Science and Technology University, Adama – Ethiopia.

7. June 2016 – Till date

Postdoctoral Research Associate under CAS President International Fellowship at Xinjiang Technical Institute of Physics, Urumqi – China.

The project entitled “Synthesis and Characterization on Deep UV and IR Nonlinear optical single crystal for structure-property relationships and devices in new optical-electronic functional materials.

Visiting:

Waseda University, Tokyo, Japan.

List of Publications:

1. Synthesis, crystal structure, and electronic structure of a new hydrated borate CsKB4O5(OH)4•2H2O single crystal:

S. Sambasivam, F. Zhang, Z. Yang, Shilie Pan

Crystal Growth & Design (Under Review, May 2018)

2. Energy Transfer Behavior and Color-tunable Properties of Ca2Al2SiO7:RE3+ (RE3+ = Tm3+,Dy3+, Tm3+/Dy3+) for White Emitting Phosphors: A. Tushagu, S. Sambasivam, Y. Wan, A. Abudoureyimu, T. Yusufu, A. Sidike J. Electronic Materials (Under minor revision, May 2018) 3. Selective voltammetric determination of Cd(II) by using N,S-codoped porous carbon nanofibers:

S. Gao, J. Liu, J. Luo, S. Sambasivam, Y. Li, X. Hu, W. Thomas, G. Hu Microchimica Acta (Accepted, April 2018)

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4. Syntheses, Crystal Structures and Characterizations of Three Alkaline Metal Borates: S. Sambasivam, L. Liu, Y. Yang, B. Bashir, Z. Yang, S. Pan Cryst.Eng.Comm. 19, 2561- 2569 (2017)

5. Size-dependent Structural, Magnetic and Optical Properties of MnCo2O4 Nanocrystallites: S. Singh, P. Pramanik, S. Sambasivam, A. Mallick, L. Giebeler, S. Thota J. Applied Physics 121, 194303 (2017)

6. Enhancement of the photoluminescence properties of Ba1.98SiO4- N2/3 :Eu0.02 phosphors and their application to green LEDs:

S. Wang, S. Sambasivam, K. N. Hui, X. L. Zhang, I. H. Kim, J. C. Park J Mater Sci: Mater Electron 27, 2809-2815 (2016).

7. Intense violet-blue emission and paramagnetism of nanocrystalline Gd3+ doped ZnO ceramics:

S. Sambasivam, D.P. Joseph, S.A. Naidu, Byung Chun Choi J. Advanced Ceramics 4, 300-306 (2015).

8. On the nature of magnetic state in the spinel Co2SnO4: S. Thota, V. Narang, S. Nayak, S. Sambasivam, B.C. Choi, T. Sarkar, M.S. Andersson R. Mathieu, M.S. Seehra

J. Physics: Condensed Matter 27, 166001 (2015).

9. Prototype electrochromic device and dye sensitized solar cell using spray deposited undoped and Li doped V2O5 thin film electrodes:

M. Kovendhan, D.P. Joseph, P. Manimuthu, S. Sambasivam, H.J. Kim, B.C. Choi, K. Asokan, C. Venkateswaran, R. Mohan

Current Applied Physics 15, 622-631(2015).

10. Structural, optical and magnetic properties of cobalt and aluminum codoped CdS nanoparticles:

G. Giribabu, G. Murali, S. Sambasivam, D.A. Reddy, R.P. Vijayalakshmi Materials Letters 126, 119-122 (2014).

11. CdS nanoflowers and interpenetrated nanorods grown on Si substrate: structural, optical properties and growth mechanism:

G. Murali, S. Sambasivam, D.A. Reddy, R.P. Vijayalakshmi Materials Chemistry and Physics 146, 399-405 (2014). 12. Ex-situ studies on calcinations of structural, optical and morphological properties of post- growth nanoparticles CeO2 by HRTEM and SAED:

B. Sathyaseelan, S. Sambasivam, T. Alagesan, K. Sivakumar Int.J. Nano Dimension 5, 341 – 349 (2014).

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13. Dopant induced RTFM and enhancement of fluorescence efficiencies in spintronic ZnS:Ni nanoparticles:

B. Poornaprakash, S. Sambasivam, D.A. Reddy, G. Murali, R.P. Vijayalakshmi, B.K. Reddy

Ceramics International 40, 2677-2684 (2014).

14. ‘Li’ doping induced physicochemical property modifications of MoO3 thin films: M. Kovendhan, D.P. Joseph, P. Manimuthu, S. Sambasivam, S.N. Karthick, K. Vijayarangamuthu, A. Sendhilkumar, K. Asokan, H.J. Kim, B.C. Choi, C. Venkateswaran, R. Mohan.

Applied Surface Science 284, 624-633 (2013).

15. Comparison of properties of pristine and 200 MeV Ag15+ ions irradiated ‘Li’ 3wt% doped V2O5 thin films:

M. Kovendhan, D.P. Joseph, P. Manimuthu, S. Sambasivam, A. Sendhilkumar, J.P. Singh, K. Asokan, C. Venkateswaran, R. Mohan.

Trans Indian Inst Met 66, 353 – 356 (2013).

16. Memory Effects and Relaxation Dynamics of MnCo2O4 Nanocrystallites: S. Thota, S.K. Das, S. Sangaraju, B.C. Choi,

IEEE Trans. Magnetics 49, 1020-1023 (2013).

17. Improved Optical and Electrical Properties of 200 MeV Ag15+ Irradiated 3 wt% ‘Li’ doped MoO3 Thin Film:

M. Kovendhan, D.P. Joseph, P. Manimuthu, S. Sambasivam, J.P. Singh, K. Asokan, C. Venkateswaran, R. Mohan

American Institute of Physics Conf. Proc. 1512, 626-627 (2013). 18. Morphology dependent luminescence from CdS nanostructures: G. Murali, D.A. Reddy, S. Sambasivam, R.P. Vijayalakshmi, B.K. Reddy, Materials Letters 93, 149-152 (2013).

19. Structural, optical and magnetic properties of single crystalline Mn3O4 nanowires: S. Sambasivam, G. Li, J.H. Jeong, B.C. Choi, K.T. Lim, and S.S. Kim J. Nanoparticle Research 14, 1138 (1-9) (2012).

20. Effect of Mn co-doping on the structural, optical and magnetic properties of ZnS:Crnanoparticles:

A. Amaranatha Reddy, S. Sambasivam, G. Murali, B. Poornaprakash, B.K. Reddy J. Alloys and Compounds 537, 208-215 (2012).

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21. Effect of Fe alloying on the structural, optical, electrical and magnetic properties of spray deposited CuO thin films:

D. Paul Joseph, S. Sambasivam, B.C. Choi, C. Venkateswaran. J. Korean Physical Society 61, 449-454 (2012).

22. Structural and optical characterization of ZnS nanoparticles co-doped with Mn and Te: A. Divya, S. Sambasivam, B.K. Reddy, and P. Sreedhara Reddy. Physica E 44, 541-545 (2011).

23. Photoluminescence and EPR studies of ZnS nanoparticles co-doped with Mn and Te: A. Divya, S. Sambasivam, B.K. Reddy, and P. Sreedhara Reddy. J. Nano-Electron. Phys. 3, 639-646 (2011).

24. Structural, morphological, and optical studies on Li doped ZnO thin films deposited by using PLD:

G. Li, S. Sambasivam, S.B. Kim, B.C. Choi, J.H. Jeong, and B.E. Jun. J. Korean Physical Society 59, 2770-2773 (2011).

25. Structural transition and blue emission in textured and highly transparent spray deposited Li doped WO3 thin films:

M. Kovendhan, D.P. Joseph, E. Sendhil Kumar, P. Manimuthu, S. Sambasivam, R. Mohan

Applied Surface Science 257, 8127-8133 (2011).

26. Antiferromagnetic interactions in Er doped SnO2 DMS nanoparticles: S. Sambasivam, D. Paul Joseph, J.H. Jeong, and B.C. Choi J. Nanoparticle Research 13, 4623-4630 (2011).

27. Spray deposited Nb2O5 thin film electrodes for fabrication of dye sensitized solar cells M. Kovendhan, D.P. Joseph, P. Manimuthu, S. Sambasivam, R. Mohan Transaction of the Indian Institute of Metals 64, 185-188 (2011). 28. Intrinsic magnetism in Fe doped SnO2 nanoparticles: S. Sambasivam, B.C. Choi, and J.G. Lin

J. Solid State Chemistry 184, 199-203 (2011).

29. Optical and ESR studies of Cd1-xCuxS (x = 0-0.15) nanoparticles passivated with thiophenol:

S. Sambasivam, J.H. Jeong, and B.C. Choi

J. Materials Research 26, 706 – 709 (2011).

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30. Effect of Er3+ doping in SnO2 semiconductor nanoparticles synthesized by solgel technique:

S. Sambasivam, S.B. Kim, J.H. Jeong, and B.C. Choi Current Applied Physics 10, 1383-1386 (2010).

31. Preparation and Characterization of ZnO Nanoparticles: B. Sathyaseelan, S. Sambasivam, B. Sreedhar, T. Alagesan, R.Jayavel and K. Jayabalan, Int. J. Nanomat. and Technology: 1, 23-27 (2010). 32. Optical and ESR studies on SnO2 nanoparticles doped with Dy3+ ions: S. Sambasivam, S.B. Kim, J.H. Jeong, B.C. Choi

Advanced Science Letters 3, 465-469 (2010).

33. Doping induced magnetism in Co – ZnS nanoparticles: S. Sambasivam, D. Paul Joseph, J. G. Lin and C. Venkateswaran, J. Solid State Chemistry: 182, 2598-2601 (2009).

34. Optical and ESR studies on Fe doped ZnS nanoparticles: S. Sambasivam, B.K. Reddy and C.K. Jayasankar,

Physics Letters A: 373, 1465-1468 (2009).

35. Structural, optical and electrical properties of luminescent (ZnS)1 x(MnTe)x powders: N. Madhusudhana Rao, G. Krishnaiah, S. Sambasivam, K. P. Reddy, D. Raja Reddy, B. K. Reddy and C. N. Xu,

J. Alloys and Compounds: 468, 360-364 (2009).

36. Synthesis and Characterization of thiophenol passivated Fe doped ZnS nanoparticles: S. Sambasivam, D. Paul Joseph, D. Raja Reddy, B. K. Reddy and C. K. Jayasankar, Materials Science and Engineering B: 150, 125 - 129 (2008). 37. Chemical synthesis and Characterization of Cu doped ZnS nanoparticles: S. Sambasivam, D. Paul Joseph, B. K. Reddy and C. K. Jayasankar, American Institute of Physics Conf. Proc. 1004, 117-121 (2008). 38. ESR and Photoluminescence properties of Cu doped ZnS nanoparticles: S. Sambasivam, D. Raja Reddy, B. K. Reddy and C. K. Jayasankar, Spectrochimica Acta Part A: 71, 1503-1506 (2008).

39. Spray deposition and characterization of nanostructured Li doped NiO thin films for application in dye-sensitized solar cells:

D. Paul Joseph, S. Sambasivam M. Saravanan, P. Renugambal,S. Philip Raja and C. Venkateswaran.

Nanotechnology: 19, 485707 (2008).

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40. EPR and magnetic properties of vapour phase grown ZnCrTe crystals: G. Krishnaiah, S. Sambasivam, B. K. Reddy,

Physics Letters A: 372, 6429-6433 (2008).

41. Synthesis and Structure of pure CdS and Mn2+ doped diluted magnetic semiconducting nanoparticles:

P. Venkatesu, S. Sambasivam, D. Raja Reddy and B. K. Reddy, Material Science Research India Vol (4) No. 3 (2007). Conferences Attended :

1. Presented research article in “Theme Meeting on Self-assembly Routes for Nanotech Materials (SARNAM – 2006)”, at Bhabha Atomic Research Centre, Mumbai, India April 26-28, 2006.

Title: Structural and Luminescence properties of Cu doped ZnS nanoparticles S. Sambasivam, D. Raja Reddy and B. K. Reddy.

2. Participated in “International Conference on Nanoscience and Nanotechnology

(ICNSNT-2006)” at University of Madras, Chennai, India, August 26 – 28, 2006. 3. Exploration of Nanocrystalline and bulk Zn0.95Co0.05O DMS, D. Paul Joseph, S. Sambasivam, S. Philip Raja and C. Venkateswaran, International Conference on Nanoscience and Technology (ICONSAT 2008), Feb. 27 to 29, 2008, Held at Convention Centre, Chennai Trade Centre, Chennai. Conducted by IGCAR, Kalpakkam.

4. 4

th

National Conference on Thermo Physical Properties (NCTP’ 07), Kollam – Kerala. Sep: 20-22, 2007. (Oral Presentation).

Title: Chemical synthesis and Characterization of Cu doped ZnS nanoparticles S. Sambasivam, D. Raja Reddy and B. K. Reddy.

5. National Conference on NCEM, Taipei, Taiwan. Jan: 7-9, 2009. (Oral Present.) Title: Structural, Optical and Magnetic studies on Fe doped SnO2 nanocrystals S. Sambasivam, J.G. Lin.

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6. 6th International Conference on ICAMP, Lijiang, China. July 17-21, 2010. Title: Optical and ESR studies on Dy doped SnO2 Semiconductor nanoparticles. S. Sambasivam, B.C. Choi.

7. International conference on the 7th Asian meeting on Ferroelectricity (AMF), Jeju Island, Korea. June 28- July 1, 2010. (Oral Presentation)

Title: Optical and Antiferromagnetic interactions on Er doped SnO2 DMS nanoparticles: An ESR and magnetic study.

S. Sambasivam, B.C. Choi.

8. 7th International symposium on Transparent Oxide thin films for Electronics and Optics

(TOEO-7), Waseda University, Tokyo, Japan. March 14-16, 2011 (Oral Presentation) Title: Effect of erbium content on the structural, morphological, and optical properties of spray deposited nanocrystalline SnO2 thin films. S. Sambasivam, B.C. Choi.

9. International conference on Nanoscience and Nanotechnology (ICNN-2012), Zurich, Switzerland. January 15-17, 2012 (Poster Presentation) Title: Effect of synthesis temperature on magnetic properties of single crystalline Mn3O4 nanowires.

S. Sambasivam, B.C. Choi.

10. National conference on Recent trends in Materiel science at S.V. Degree and P.G College, Kadapa on March 1-2, 2015 (Poster presentation) Title: Repercussion of Mn doping on structural and magnetic properties of SnO2 nanoparticles:

K. Subramanyam, S. Sambasivam, B. Poornaprakash, S. Ramu, R.P. Vijayalakshmi. Workshop Attended :

Awareness workshop on “Low Temperature and High Magnetic Field Facilities at CSR Indore” at Indore, India, during December 10 -12, 2007. Research Expertise:

Expertise in operating XRD - Siefert 3003TT X-ray Diffractometer.

Expertise in operating ESR - the Bruker EMX spectometer

Expertise in operating Thermo Nicolet-5700 Fourier Transform Infra-Red (FTIR) Spectrophotometer.

Expertise in operating Jasco UV-Vis-NIR Absorption Spectrophotometer.

Expertise in operating Photoluminescence spectra, Jobin Yvon Fluorolog – 3 Spectrophotometer.

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Experimental Techniques known & Instruments handled Preparation of nanocrystalline samples using chemical coprecipitation, ball milling, and sol-gel methods.

Preparation of bulk samples using solid state reaction method Thin films deposition using Spray Pyrolysis technique, CVD Data analysis for X-ray diffraction

Microstructural analysis using SEM and TEM

High temperature furnaces

Vacuum pump units

Vacuum sealing

Preparation of single crystal phosphors by Flux and Bridgman growth technique. Preparation of Pt- based oxides nanomaterials by Flame aerosol synthesis. 12

Academic Plan of Research and Teaching

Keeping the future energy needs/demand in view, my entire research career was focused on developing energy efficient materials for Solid State Lighting (SSL), Dye- sensitized solar cells, and catalysts for solid oxide fuel cells. SSL uses light emitting diodes and inorganic luminescent materials to create a white light. It is expected that by the year 2030 the world energy consumption for general illumination could be reduced to 50%. I have been working on flame aerosol synthesis of Pt-based catalysts for electrodesin solid oxide fuel cells.

My research in near future will focus on synthesis of quantum dots and single crystals of inorganic luminescent materials to be used for the fabrication of solid state lighting devices. The futuristic scope for the inorganic luminescent materials is to prepare fine particles, since the fine particles can easily mix with epoxy to coat diode surface. It is known that the bulk material is hard to disperse homogeneously in epoxy whereas the nanocrystallites have many surface defects and which is a killer for luminescence efficiency. So the ultimate solution is to prepare quantum dots of the binary and ternary luminescent materials. It is known that quantum dots will have maximum efficiency and possibility of having quantum efficiency >1. Next, the development of renewable energy is a major issue, and photovoltaic energy conversion appears as a promising alternative to fossil energy, mainly due to non-toxic and non-polluting operation, as well as to an inexhaustible resources. Inorganic semiconductors are ideal for fabricating highly efficient solar cells, as they can absorb a broad range of light and transport charge effectively. On the other hand, conducting polymers have been successfully used as active materials to construct a variety of electronic and electro optical devices such as field-effect transistors, light-emitting devices, and solar cells. I have been working on the synthesis of metal oxides semiconductors, conducting polymers and their nanocomposites of different morphologies and dimensions for the promising applications in dye sensitized solar cells (DSSCs), organic solar cells, hybrid solar cells, heterostructure devices and heterostructure diodes. Besides, these nanomaterials have also been applied as chemical sensors for the detection of harmful and toxic chemicals. 13

Secondly, nanocrystallites of magnetic-semiconductor oxides. It is proposed to establish good reproducible steps for stabilization of ferromagnetism in semiconductor oxides by doping various magnetic dopants. Despite the fact that the bulk and thin films are processed differently, the data derived from nanocrystalline samples will provide clues for settling controversies regarding the magnetic phase in diluted magnetic semiconductors. The objectives of my teaching are to prepare students with firm and extensive knowledge with productive abilities and high diathesis of science especially in the engineering stream. I could prefer to teach the fundamentals and key aspects of the subjects as the students would visualize, explore, develop and clarify their scientific ideas in images. This fundamental teaching would impart a generative knowledge of the subject. I’m very passionate to transfer my physics and materials science knowledge to the young minds. My interests are teaching on Solid State Physics- Semiconductor Physics and Physics of Nanomaterials; Crystal growth – processing and techniques; advanced techniques for Materials Characterization; Surface Engineering.

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References:

1. Prof. C. K. Jayasankar

Department of Physics

Sri Venkateswara University,

Tirupati – 517 502, India

ac5lta@r.postjobfree.com

2. Prof. Byung Chun Choi

Department of Physics

Pukyong National University

Daeyon-3 Dong, Namgu

Busan – 608 737, South Korea

ac5lta@r.postjobfree.com

3. Dr. B. Sreedhar

Principal Scientist

Inorganic and Physical Chemistry Division

Indian Institute of Chemical Technology [IICT]

Tarnaka, Hyderabad-500607, INDIA

ac5lta@r.postjobfree.com

DECLARATION

I hereby declare that the above furnished particulars are correct and true to the best of my knowledge.

Place: Urumqi, China.

Date : 11- 05- 2018. (S. SAMBASIVAM)

Statement of Research:

I would like to provide a brief note about my experience during the thesis and postdoctoral studies. My research experience is primarily focused on synthesis of semiconducting oxide, sulfide nanomaterials, bulk and thin films and studies their physical properties namely optical, magnetic, and solar cells, Photonic devices, and Deep UV and IR Nonlinear optical properties. My expertise also includes various advanced materials characterization and interpretation of the results. Here I am giving future area of research work plan. 1. Nonlinear Optical Properties:

Nonlinear Optical (NLO) materials have become increasingly important and are attracting more and more attention owing to their promising applications in laser science and technology. The design, synthesis and characterization of materials for NLO applications are emerging as multidisciplinary new frontier of science and technology, capturing the imagination of scientists and engineers worldwide. Many excellent NLO materials have been reported including KDP, ADP, LiNbO3, KBBF (KBe2BO3F2) etc. Among them, some have realized commercialization (such as KTP (KTiOPO4), BBO (BaB2O4) and LBO (LiB3O5)). However, the growth period of these crystals is relatively long, normally lasting for one to two months. Phosphides and sulfides such as ZnGeP2, CdSiP2, LiInS2, and AgGaSe2 are considered to be excellent infrared optical crystals, but there are still serious drawbacks due to high vapor pressure (of P, S and Se) which limit their application. Therefore, continuous interest has been paid in developing new crystals with improved linear and nonlinear optical properties, including higher nonlinear coefficients, wider transmission ranges, more flexible phase-matching properties, enhanced optical damage tolerance and chemical, thermal, and mechanical stability. The main goal of the proposed is to develop rare earth based calcium oxyborate and fluoroborate single crystals towards more effective nonlinear optical performance, study their structural, basic optical properties and apply their properties in the fabrication of SHG devices. The objectives of the work will be

1. To grow good quality bulk size Calcium rare earth borates (ReCOB where Re= Rare earth elements) TmCOB and TmxY1-xCOB single crystals. 2. To grow good quality bulk size fluoroborates, Ba3B6O11F2 and Ba4B11O20F single crystals.

3. To optimize the growth parameters to get high quality transparent and large single crystals of the proposed materials by Czochralski process (vertical pulling method) and Top Seeded Solution Growth Techniques.

4. To dope with rare earth metals, since the doping by an appropriate ion was found to be an effective method to tune the birefringence of the material. 5. To analyze and confirm the structural and crystalline perfection of the grown crystals using X ray diffractometer and Topography

6. To estimate the basic optical, nonlinear optical characteristics of the grown crystals. 7. To demonstrate Second Harmonic generation (SHG) using the grown crystals. 2. Energy Efficient Applications:

Keeping the future energy needs/demand in view, my entire research career was focused on developing energy efficient materials for Solid State Lighting (SSL), Dye-sensitized solar cells, and catalysts for solid oxide fuel cells. SSL uses light emitting diodes and inorganic luminescent materials to create a white light. It is expected that by the year 2030 the world energy consumption for general illumination could be reduced to 50%. My research in near future will focus on synthesis of quantum dots and single crystals of inorganic luminescent materials to be used for the fabrication of solid state lighting devices. The futuristic scope for the inorganic luminescent materials is to prepare fine particles, since the fine particles can easily mix with epoxy to coat diode surface. It is known that the bulk material is hard to disperse homogeneously in epoxy whereas the nanocrystallites have many surface defects and which is a killer for luminescence efficiency. So the ultimate solution is to prepare quantum dots of the binary and ternary luminescent materials. It is known that quantum dots will have maximum efficiency and possibility of having quantum efficiency >1. Next, the development of renewable energy is a major issue, and photovoltaic energy conversion appears as a promising alternative to fossil energy, mainly due to non-toxic and non-polluting operation, as well as to an inexhaustible resources. Inorganic semiconductors are ideal for fabricating highly efficient solar cells, as they can absorb a broad range of light and transport charge effectively. On the other hand, conducting polymers have been successfully used as active materials to construct a variety of electronic and electro optical devices such as field-effect transistors, light-emitting devices, and solar cells. I have been working on the synthesis of metal oxides semiconductors, conducting polymers and their nanocomposites of different morphologies and dimensions for the promising applications in dye sensitized solar cells (DSSCs), organic solar cells, hybrid solar cells, heterostructure devices and heterostructure diodes. Besides, these nanomaterials have also been applied as chemical sensors for the detection of harmful and toxic chemicals. 3. Rare-earth doped nanocrystalline materials for photonic and sensor devices: Much attention has been paid to develop RE3+-doped transparent nanoglass ceramics (TNGCs) containing fluoride nanocrystals and nanocrystalline powders for photonic, phosphor and sensor applications. Therefore, the goal of this work is the optimization of luminescence properties in nanocrystalline powders and glasses with different compositions and further improvements in luminescence if these glasses were converted to nanoglass ceramics by heat treatment. Identification and preparation of optically active trivalent rare earth (RE3+)-doped new transparent nanoglass-ceramics containing fluoride nanocrystals (SiO2-Al2O3-MO-MF2-REF3, SiO2-Al2O3-RO-MO-MF2-REF3, where RO= Bi2O3, TiO2 or P2O5 and M=Mg, Ca, Sr or Ba) and development of RE3+-doped ABO3 garnet (LaAlO3, YAlO3, GdAlO3, YGaO3, etc.) nanocrystalline powders for photonic, sensor and phosphor applications. The optimized systems will also be characterized under extreme conditions (pressure and temperature) to develop pressure/temperature sensors.

The transparent nanocrystalline glass-ceramics (TNGCs) are formed through the controlled nucleation and crystallization of glasses. RE3+-doped oxyfluoride glasses of identified composition are prepared by melt quenching method at a suitable temperature and duration. The precursor glasses are then annealed systematically around crystallization temperature to induce fluoride nanocrystals in the glasses to get TNGCs. RE3+-doped ABO3 nanocrystalline powders are prepared using sol-gel method. Stoichiometric molar ratios of suitable high purity metal nitrates are dissolved in 1M HNO3 under stirring and heating at appropriate temperature



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